357 resultados para livscykelanalys (LCA)


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Purpose: To report the clinical and genetic study of a family with Leber congenital amaurosis (LCA). Methods: We studied a consanguineous family from Yemen in which three individuals were affected with LCA. Genomic DNA was prepared from venous leukocytes. Linkage analysis of all family members using polymorphic markers flanking the known LCA genes was performed, followed by direct sequencing of all the exons and intron-exon junctions of the RPE65 gene. Results: The three affected were 5, 8 and 12 years old. Severe visual impairment and night blindness were noticed during infancy. Nystagmus was not a feature. Photophobia was only observed in the 8-year-old patient. The 5-year old youngest affected had a bilateral hyperopia of +3.50 and a visual acuity of 1/60. The oldest two had mild myopia and visual acuity limited to hand movements RE and counting fingers LE for the oldest and of 5/60 OD, 6/60 OS for the other. On fundus examination, they harbored common clinical features such as disc pallor, attenuated vessels, white flecks in the retina mid-periphery and bull's eye maculopathy. Electroretinograms of the oldest child were completely extinguished while residual scotopic responses with abolished photopic and flicker responses were observed in the two youngest. Sequencing identified a novel missense mutation, IVS2-3C>G, in the second RPE65 intron. The mutation was not detected in 80 ethnically matched normal individuals. Conclusion: We have identified a novel LCA-related homozygous RPE65 mutation associated with a severe clinical presentation including an early and severe cone dysfunction. This is in contrast with the presentation associated with other RPE65 mutations predominantly causing a rod-cone dystrophy with residual cone function. The identified mutation potentially affects splicing of the third exon and could result in a loss of function. Definite functional consequences of this change still need to be characterized.

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In three-dimensional (3D) coronary magnetic resonance angiography (MRA), the in-flow contrast between the coronary blood and the surrounding myocardium is attenuated as compared to thin-slab two-dimensional (2D) techniques. The application of a gadolinium (Gd)-based intravascular contrast agent may provide an additional source of signal and contrast by reducing T(1blood) and supporting the visualization of more distal or branching segments of the coronary arterial tree. In six healthy adults, the left coronary artery (LCA) system was imaged pre- and postcontrast with a 0.075-mmol/kg bodyweight dose of the intravascular contrast agent B-22956. For imaging, an optimized free-breathing, navigator-gated and -corrected 3D inversion recovery (IR) sequence was used. For comparison, state-of-the-art baseline 3D coronary MRA with T(2) preparation for non-exogenous contrast enhancement was acquired. The combination of IR 3D coronary MRA, sophisticated navigator technology, and B-22956 allowed for an extensive visualization of the LCA system. Postcontrast, a significant increase in both the signal-to-noise ratio (SNR; 46%, P < 0.05) and contrast-to-noise ratio (CNR; 160%, P < 0.01) was observed, while vessel sharpness of the left anterior descending (LAD) artery and the left coronary circumflex (LCX) were improved by 20% (P < 0.05) and 18% (P < 0.05), respectively.

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Purpose: Despite the fundamental role of ecosystem goods and services in sustaining human activities, there is no harmonized and internationally agreed method for including them in life cycle assessment (LCA). The main goal of this study was to develop a globally applicable and spatially resolved method for assessing land-use impacts on the erosion regulation ecosystem service.Methods: Soil erosion depends much on location. Thus, unlike conventional LCA, the endpoint method was regionalized at the grid-cell level (5 arc-minutes, approximately 10×10 km2) to reflect the spatial conditions of the site. Spatially explicit characterization factors were not further aggregated at broader spatial scales. Results and discussion: Life cycle inventory data of topsoil and topsoil organic carbon (SOC) losses were interpreted at the endpoint level in terms of the ultimate damage to soil resources and ecosystem quality. Human health damages were excluded from the assessment. The method was tested on a case study of five three-year agricultural rotations, two of them with energy crops, grown in several locations in Spain. A large variation in soil and SOC losses was recorded in the inventory step, depending on climatic and edaphic conditions. The importance of using a spatially explicit model and characterization factors is shown in the case study.Conclusions and outlook: The regionalized assessment takes into account the differences in soil erosion-related environmental impacts caused by the great variability of soils. Taking this regionalized framework as the starting point, further research should focus on testing the applicability of the method trough the complete life cycle of a product and on determining an appropriate spatial scale at which to aggregate characterization factors, in order to deal with data gaps on location of processes, especially in the background system. Additional research should also focus on improving reliability of the method by quantifying and, insofar as it is possible, reducing uncertainty.

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The environmental impact of the water consumption of four typical crop rotations grown in Spain, including energy crops, was analyzed and compared against Spanish agricultural and natural reference situations. The life cycle assessment (LCA) methodology was used for the assessment of the potential environmental impact of blue water (withdrawal from water bodies) and green water (uptake of soil moisture) consumption. The latter has so far been disregarded in LCA. To account for green water, two approaches have been applied: the first accounts for the difference in green water demand of the crops and a reference situation. The second is a green water scarcity index, which measures the fraction of the soil-water plant consumption to the available green water. Our results show that, if the aim is to minimize the environmental impacts of water consumption, the energy crop rotations assessed in this study were most suitable in basins in the northeast of Spain. In contrast, the energy crops grown in basins in the southeast of Spain were associated with the greatest environmental impacts. Further research into the integration of quantitative green water assessment in LCA is crucial in studies of systems with a high dependence on green water resources.

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Purpose: To describe the genotype/phenotype correlation associated with homozygous p.R108X mutation in the SPATA7 gene. Methods: A consanguineous nuclear family of Ethiopian origin was ascertained for genotypic and phenotypic characterization, including fundus photography, fundus autofluorescence (FAF), and full-field ERG. Molecular diagnosis was performed using a microarray. Results: Two of the 5 family members were affected with LCA. A homozygous c.322C>T (p.R108X) mutation in exon 5 of SPATA-7 was identified in both of them. The patients were 4 and 11 years old, respectively. Fundus examination revealed an unremarkable macular area, but optic nerve pallor, attenuated vascular calibre and deep retinal nummular deposits with para-arterial sparing predominant in the midperiphery. FAF showed multiples areas of hyperautofluorescence, corresponding to the deep retinal deposits. ERG was not recordable in the young patient, and showed severe rods/cones dysfunction in the older one. Conclusions: The literature describing genotype/phenotype correlation of SPATA-7 mutations in Leber congenital amaurosis (LCA) is still limited. We report the occurrence of para-arterial sparing in two sibs with SPATA7-linked LCA which may represent a clinical marker of this condition.

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El presente proyecto tiene por objetivo realizar una propuesta de cultivo de manzano (Malus domestica) en la Vall d’Alinyà para el desarrollo de un producto agroalimentario que contribuya a la revitalización de esta área rural y a la mitigación del calentamiento global. Para ello, se pretende proporcionar una metodología para calcular, con mayor precisión, el comportamiento de los cultivos como sumidero de carbono a partir del balance neto de gases con efecto invernadero (GEI) del sistema. Con tal de obtener las emisiones de GEI generadas por los cultivos se desarrolla un análisis del ciclo de vida (ACV), y para obtener la fijación de los cultivos, se realiza un análisis de su capacidad de absorción de dióxido de carbono en la biomasa de la plantación. Además, mediante el uso de sistemas de información geográfica (SIG), se determinaron los terrenos potenciales para el cultivo del manzano en la zona de estudio. Posteriormente, se verifica la certificación de créditos en el mercado de carbono voluntario y se analiza la viabilidad económica del proyecto, obteniendo así un producto (la manzana) con valor ambiental añadido. Como conclusión se obtuvo una viabilidad positiva de la verificación de créditos, puesto que el balance neto de carbono fue positivo, absorbiéndose 234,54 t CO2 en todo el territorio potencialmente cultivable (16,92 ha) y durante 15 años de actividad agrícola. Al mismo tiempo, la propuesta resultó viable económicamente, generándose unos beneficios ligados a la venta de producción frutícola y de los créditos de carbono de 79.484 € durante los 15 años de actividad productiva.

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Pathogenesis in the Rpe65(-/-) mouse model of Leber's congenital amaurosis (LCA) is characterized by a slow and progressive degeneration of the rod photoreceptors. On the opposite, cones degenerate rapidly at early ages. Retinal degeneration in Rpe65(-/-) mice, showing a null mutation in the gene encoding the retinal pigment epithelium 65-kDa protein (Rpe65), was previously reported to depend on continuous activation of a residual transduction cascade by unliganded opsin. However, the mechanisms of apoptotic signals triggered by abnormal phototransduction remain elusive. We previously reported that activation of a Bcl-2-dependent pathway was associated with apoptosis of rod photoreceptors in Rpe65(-/-) mice during the course of the disease. In this study we first assessed whether activation of Bcl-2-mediated apoptotic pathway was dependent on constitutive activation of the visual cascade through opsin apoprotein. We then challenged the direct role of pro-apoptotic Bax protein in triggering apoptosis of rod and cone photoreceptors.Quantitative PCR analysis showed that increased expression of pro-apoptotic Bax and decreased level of anti-apoptotic Bcl-2 were restored in Rpe65(-/-)/Gnat1(-/-) mice lacking the Gnat1 gene encoding rod transducin. Moreover, photoreceptor apoptosis was prevented as assessed by TUNEL assay. These data indicate that abnormal activity of opsin apoprotein induces retinal cell apoptosis through the Bcl-2-mediated pathway. Following immunohistological and real-time PCR analyses, we further observed that decreased expression of rod genes in Rpe65-deficient mice was rescued in Rpe65(-/-)/Bax(-/-) mice. Histological and TUNEL studies confirmed that rod cell demise and apoptosis in diseased Rpe65(-/-) mice were dependent on Bax-induced pathway. Surprisingly, early loss of cones was not prevented in Rpe65(-/-)/Bax(-/-) mice, indicating that pro-apoptotic Bax was not involved in the pathogenesis of cone cell death in Rpe65-deficient mice.This is the first report, to our knowledge, that a single genetic mutation can trigger two independent apoptotic pathways in rod and cone photoreceptors in Rpe65-dependent LCA disease. These results highlight the necessity to investigate and understand the specific death signaling pathways committed in rods and cones to develop effective therapeutic approaches to treat RP diseases.

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Life cycle analyses (LCA) approaches require adaptation to reflect the increasing delocalization of production to emerging countries. This work addresses this challenge by establishing a country-level, spatially explicit life cycle inventory (LCI). This study comprises three separate dimensions. The first dimension is spatial: processes and emissions are allocated to the country in which they take place and modeled to take into account local factors. Emerging economies China and India are the location of production, the consumption occurs in Germany, an Organisation for Economic Cooperation and Development country. The second dimension is the product level: we consider two distinct textile garments, a cotton T-shirt and a polyester jacket, in order to highlight potential differences in the production and use phases. The third dimension is the inventory composition: we track CO2, SO2, NO (x), and particulates, four major atmospheric pollutants, as well as energy use. This third dimension enriches the analysis of the spatial differentiation (first dimension) and distinct products (second dimension). We describe the textile production and use processes and define a functional unit for a garment. We then model important processes using a hierarchy of preferential data sources. We place special emphasis on the modeling of the principal local energy processes: electricity and transport in emerging countries. The spatially explicit inventory is disaggregated by country of location of the emissions and analyzed according to the dimensions of the study: location, product, and pollutant. The inventory shows striking differences between the two products considered as well as between the different pollutants considered. For the T-shirt, over 70% of the energy use and CO2 emissions occur in the consuming country, whereas for the jacket, more than 70% occur in the producing country. This reversal of proportions is due to differences in the use phase of the garments. For SO2, in contrast, over two thirds of the emissions occur in the country of production for both T-shirt and jacket. The difference in emission patterns between CO2 and SO2 is due to local electricity processes, justifying our emphasis on local energy infrastructure. The complexity of considering differences in location, product, and pollutant is rewarded by a much richer understanding of a global production-consumption chain. The inclusion of two different products in the LCI highlights the importance of the definition of a product's functional unit in the analysis and implications of results. Several use-phase scenarios demonstrate the importance of consumer behavior over equipment efficiency. The spatial emission patterns of the different pollutants allow us to understand the role of various energy infrastructure elements. The emission patterns furthermore inform the debate on the Environmental Kuznets Curve, which applies only to pollutants which can be easily filtered and does not take into account the effects of production displacement. We also discuss the appropriateness and limitations of applying the LCA methodology in a global context, especially in developing countries. Our spatial LCI method yields important insights in the quantity and pattern of emissions due to different product life cycle stages, dependent on the local technology, emphasizing the importance of consumer behavior. From a life cycle perspective, consumer education promoting air-drying and cool washing is more important than efficient appliances. Spatial LCI with country-specific data is a promising method, necessary for the challenges of globalized production-consumption chains. We recommend inventory reporting of final energy forms, such as electricity, and modular LCA databases, which would allow the easy modification of underlying energy infrastructure.

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Background, aim, and scope A coupled Life Cycle Costing and life cycle assessment has been performed for car-bodies of the Korean Tilting Train eXpress (TTX) project using European and Korean databases, with the objective of assessing environmental and cost performance to aid materials and process selection. More specifically, the potential of polymer composite car-body structures for the Korean Tilting Train eXpress (TTX) has been investigated. Materials and methods This assessment includes the cost of both carriage manufacturing and use phases, coupled with the life cycle environmental impacts of all stages from raw material production, through carriage manufacture and use, to end-of-life scenarios. Metallic carriages were compared with two composite options: hybrid steel-composite and full-composite carriages. The total planned production for this regional Korean train was 440 cars, with an annual production volume of 80 cars. Results and discussion The coupled analyses were used to generate plots of cost versus energy consumption and environmental impacts. The results show that the raw material and manufacturing phase costs are approximately half of the total life cycle costs, whilst their environmental impact is relatively insignificant (3-8%). The use phase of the car-body has the largest environmental impact for all scenarios, with near negligible contributions from the other phases. Since steel rail carriages weigh more (27-51%), the use phase cost is correspondingly higher, resulting in both the greatest environmental impact and the highest life cycle cost. Compared to the steel scenario, the hybrid composite variant has a lower life cycle cost (16%) and a lower environmental impact (26%). Though the full composite rail carriage may have the highest manufacturing cost, it results in the lowest total life cycle costs and lowest environmental impacts. Conclusions and recommendations This coupled cost and life cycle assessment showed that the full composite variant was the optimum solution. This case study showed that coupling of technical cost models with life cycle assessment offers an efficient route to accurately evaluate economic and environmental performance in a consistent way.

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Many Spanish destinations are now considering low cost airlines (LCA) important for attracting tourists. However, there is little evidence on the characteristics travelers using low cost airlines and their flight preferences. Typical segmentation of air travelers are business versus leisure travelers and business versus tourist fares. The aim of this paper is to obtain a deeper understanding of the demand of LCA through a segmentation analysis, based on 808 foreign travelers who used Girona airport, that focuses on low cost travelers’ valuations of different flight attributes and trip related characteristics

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Life cycle analysis (LCA) is a comprehensive method for assessing the environmental impact of a product or an activity over its entire life cycle. The purpose of conducting LCA studies varies from one application to another. Different applications use LCA for different purposes. In general, the main aim of using LCA is to reduce the environmental impact of products through guiding the decision making process towards more sustainable solutions. The most critical phase in an LCA study is the Life Cycle Impact Assessment (LCIA) where the life cycle inventory (LCI) results of the considered substances related to the study of a certain system are transformed into understandable impact categories that represent the impact on the environment. In this research work, a general structure clarifying the steps that shall be followed ir order to conduct an LCA study effectively is presented. These steps are based on the ISO 14040 standard framework. In addition, a survey is done on the most widely used LCIA methodologies. Recommendations about possible developments and suggetions for further research work regarding the use of LCA and LCIA methodologies are discussed as well.

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The close relationship between the chlorophyll-meters readings and the total chlorophyll and nitrogen contents in leaves, has allowed their evaluation both in annual and perennial species. Besides, some physiological events such as the CO2 assimilation have also been estimated by chlorophyll meters. This work was carried out aiming to evaluate the gas exchanges of peach palms as a function of the chlorophyll SPAD-Meter readings. Three year-old peach palms from Yurimaguas, Peru were studied in Ubatuba, SP, Brazil, spaced 2 x 1 m in area under a natural gradient of organic matter which allowed four plots to be considered, according to the peach palms leaves colors, from light yellow to dark green. The SPAD readings and the stomatal frequency of leaflets were evaluated. The photosynthetic photon flux density (PPFD, μmol m-2 s-1), the leaf temperature (Tleaf, ºC), the CO2 assimilation (A, μmol m-2 s-1), the stomatal conductance (g s, mol m-2 s-1), the transpiration (E, mmol m-2 s-1) and the intercellular CO2 concentration (Ci, μmol mol-1) were evaluated with a portable infrared gas analyzer (LCA-4, ADC BioScientific Ltd., Great Amwell, U.K.). A linear increase in the CO2 assimilation as a function of the SPAD readings (y = -0.34 + 0.19x, R² = 0.99), indicates that they can be a rapid and cheap complementary method to evaluate in peach palms some important physiological events, such as CO2 assimilation.

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Diplomityössä tutkittiin elinkaariarvioinnin ja sillä saatavien tulosten käyttöä ympäristömyötäisen tuotesuunnittelun tukena. Työn alussa kuvaillaan niitä asioita, jotka yhdistävät yrityksen ympäristöasioihin. Työn aikana suoritettiin kahden yritysten tuotteille elinkaariarvioinnit. Näistä tutkimuksista saatuja käytännön kokemuksia on käytetty diplomityössä. Pääpainopiste käytännön kokemuksissa oli itse elinkaariarvioinnin tekemisessä esille tulleissa seikoissa sekä tulosten tulkinnassa ympäristömyötäisen tuotesuunnittelun tavoitteiden asettamisen näkökulmasta. Ympäristömyötäisen tuotesuunnittelun tavoitteet ovat: materiaali- ja energiakulutuksen vähentäminen, kierrätettävyyden parantaminen, tuotteen käyttöiän pidentäminen ja ympäristölle haitallisten raaka-aineiden välttäminen. Jokaisella ympäristömyötäisen tuotesuunnittelun tavoitteella on oma erityispiirteensä, joka on huomioitava elinkaariarviointia käytettäessä. Työn aikana havaittiin, että erityinen huomio on kiinnitettävä lähtötietojen keruuvaiheeseen. Vielä nykyään on vaikea saada, etenkin alihankkijoilta, kaikkia tarvittavia inventaariotietoja. Tähän elinkaariarvioinnin suorittamisen kannalta ratkaisevaan vaiheeseen, on kaikkien osapuolten kiinnitettävä tulevaisuudessa huomiota. Myös tulosten tulkintaan kiinnitettiin huomioita. Merkittävien tekijöiden ja niihin vaikutusmahdollisuuksien havaitseminen on tärkeä osa tavoitteiden asettamista. Hyvin perusteltujen tavoitteiden asettamisen edellytys on kattavat ja luotettavat elinkaariarvioinnin tulokset. Nämä taas edellyttävät riittävän laajoja, laadukkaita ja yhdenmukaisia lähtötietoja, joita vielä nykyään on harvoin saatavilla.

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Taloudellisen laskennan yhdistäminen elinkaariarviointiin (LCA) on alkanut kiinnostaa eri teollisuuden aloja maailmanlaajuisesti viime aikoina. Useat LCA-tietokoneohjelmat sisältävät kustannuslaskentaominaisuuksia ja yksittäiset projektit ovat yhdistäneet ympäristö- ja talouslaskentamenetelmiä. Tässä projektissa tutkitaan näiden yhdistelmien soveltuvuutta suomalaiselle sellu- ja paperiteollisuudelle, sekä kustannuslaskentaominaisuuden lisäämistä KCL:n LCA-ohjelmaan, KCL-ECO 3.0:aan. Kaikki tutkimuksen aikana löytyneet menetelmät, jotka yhdistävät LCA:n ja taloudellista laskentaa, on esitelty tässä työssä. Monet näistä käyttävät elinkaarikustannusarviointia (LCCA). Periaatteessa elinkaari määritellään eri tavalla LCCA:ssa ja LCA:ssa, mikä luo haasteita näiden menetelmien yhdistämiselle. Sopiva elinkaari tulee määritellä laskennan tavoitteiden mukaisesti. Työssä esitellään suositusmenetelmä, joka lähtee suomalaisen sellu- ja paperiteollisuuden erikoispiirteistä. Perusvaatimuksena on yhteensopivuus tavanomaisesti paperin LCA:ssa käytetyn elinkaaren kanssa. Menetelmän yhdistäminen KCL-ECO 3.0:aan on käsitelty yksityiskohtaisesti.

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La recerca analitza quines són les claus actuals de l’ús dela LCa Catalunya. Per fer-ho, primer de tot explica quina és la realitat de les polítiques criminals i d’execució penal practicades a Catalunya i a Espanya i les compara amb altres realitats europees. Els resultats d’aquesta primera part fonamenten la conveniència de fer augmentar de manera significativa la seva aplicació i com aquest augment repercutiria positivament en la millora de les taxes de reincidència, en el desistiment del delicte i en la reinserció social de les persones encarcerades. En la segona part de l’estudi s’analitza el perfil de les persones que arriben a la LC però també de les que no hi arriben, tot i complir algunes de les condicions objectives per fer-ho. De l’estudi d’aquests perfils s’analitzen les similituds i diferències en les característiques dels penats i es fan propostes de millora en la classificació de grau penitenciari i la possibilitat de progressió sense que augmenti el risc teòric de reincidència ni el de recursos a assignar, tot i que sí resulti necessari pensar i fer-ne una redistribució dels actualment existents. La tercera part de l’estudi es dedica a analitzar els obstacles que té l’Administració per poder fer propostes de millora per augmentar la seva implementació. Entre les dificultats analitzades es comenten: el model d’aplicació espanyol sobre la LC, la satisfacció de la responsabilitat civil, els estrangers que es troben en situació administrativa irregular a Espanya, els retards en la concessió dels permisos ordinaris i les progressions de grau i el seguiment i control de la LC. L’estudi ha fet servir metodologies quantitatives i qualitatives simultàniament. La informació obtinguda es triangula i s’assenyalen aquells punts on el consens és més global i aquells punts més controvertits on els resultats no permeten extreure’n conclusions fefaents. En la part quantitativa s’han analitzat utilitzant diferents tècniques estadístiques 3.340 casos que es trobaven l’any 2012 en LC, 3r grau i 2n grau. En la part qualitativa, s’ha fet anàlisi de casos, entrevistes en profunditat, grups focals, tècnica Delphi i recull bibliogràfic i de legislació comparada. La recerca acaba proposant 23 propostes de millora agrupades en 6 blocs d’intervenció.